Matthew Boulton FRS (3 September 1728 – 17 August 1809) is an English manufacturer and business partner of Scottish engineer James Watt.

In the final quarter of the 18th century, the partnership installs hundreds of Boulton & Watt steam engines, which are a great advance on the state of the art, making possible the mechanization of factories and mills.

Boulton applies modern techniques to the minting of coins, striking millions of pieces for Britain and other countries, and supplying the Royal Mint with up-to-date equipment.

Born in Birmingham, England in 1728, Boulton is the son of a Birmingham manufacturer of small metal products who dies when Boulton is 31.

By this time, Boulton has managed the business for several years, and thereafter expands it considerably, consolidating operations at the Soho Manufactory, built by him near Birmingham.

At Soho, he adopts the latest techniques, branching into silver plate, ormolu and other decorative arts.

He becomes associated with James Watt when Watt's business partner, John Roebuck, is unable to pay a debt to Boulton, who accepts Roebuck's share of Watt's patent as settlement.

He then successfully lobbies Parliament to extend Watt's patent for an additional 17 years, enabling the firm to market Watt's steam engine.

The firm installs hundreds of Boulton & Watt steam engines in Britain and abroad, initially in mines and then in factories.

Boulton is a key member of the Lunar Society, a group of Birmingham-area men prominent in the arts, sciences, and theology.

Members include Watt, Erasmus Darwin, Josiah Wedgwood and Joseph Priestley.

The Society meets each month near the full moon.

Members of the Society have been given credit for developing concepts and techniques in science, agriculture, manufacturing, mining, and transport that laid the groundwork for the Industrial Revolution.

Boulton founds the Soho Mint, to which he soon adapts steam power.

He seeks to improve the poor state of Britain's coinage, and after several years of effort obtains a contract in 1797 to produce the first British copper coinage in a quarter century.

His "cartwheel" pieces are well-designed and difficult to counterfeit, and include the first striking of the large copper British penny, which continues to be coined until decimalization in 1971.

He retires in 1800, though continuing to run his mint, and dies in 1809.

His image appears alongside that of James Watt on the Bank of England £50 note.